Catalyst precursor composition for electroless plating, and preparation method of transparent electromagnetic interference shielding material using the same

ABSTRACT

The present invention relates to a catalyst precursor composition for electroless plating, and more specifically, the present invention provides the catalyst precursor composition comprising (a) a reactive oligomer; (b) a reactive monomer; (c) a photoinitiator; (d) a catalyst precursor for electroless plating; and (e) a solvent, and a method of preparing the EMI shielding material with the same. 
     The present invention provides an easy and simple method of preparing the EMI shielding material by using the catalyst precursor composition that contains a UV curable resin with good adhesion to the base material, thereby eliminating the need for pre-treating the base material with a receptive layer before electroless plating.

BACKGROUND OF THE INVENTION

(a) Field of the Invention

The present invention relates to a catalyst precursor composition forelectroless plating, and a method of preparing transparentelectromagnetic interference shielding material (hereinafter, referredto as “EMI” shielding material) using the same. More specifically, thecatalyst precursor composition includes a UV (ultraviolet) curable resinwith excellent adhesiveness to a base material, thereby eliminating theneed for an additional pre-treatment in preparing the EMI shieldingmaterial. Thus, the present invention provides a catalyst precursorcomposition to easily prepare the EMI shielding material, and apreparation method for EMI shielding material using the same.

(b) Description of the Related Art

A plasma display panel (hereinafter referred to as “PDP”) has anelectrode providing a whole surface of a front glass thereof withsignals and electric power, which produces much electromagneticradiation in operation compared to other display devices.

Thus, it is necessary for the PDP to be equipped with a filter forshielding harmful electromagnetic waves generated in operating the PDP.The filter consists of several films laminated on glass, such as ananti-reflection film (hereinafter referred to as “AR film”), a nearinfrared ray shield film (hereinafter referred to as “NIR film”), aNeon-cut film, an EMI shield film, etc.

The EMI shielding material with good transparency is preferable toenable penetration of visible light. The EMI shielding material can beprepared by adhering conductive metals such as Copper, Silver, andNickel on a transparent base material in a lattice pattern. The adheringmethods of conductive metals on a substrate are classified into a drymethod including a sputtering method and vacuum deposition, and a wetmethod including electroless plating, etc. Because the dry methodrequires expensive manufacturing equipments, the inexpensive wet methodis most widely used.

In the electroless plating method, the plating reaction is initiated bycontacting a plating solution with a catalyst, and thus metal is onlyplated on the catalyst. Printing of the catalyst on the transparent basematerial in a lattice pattern and then performing electroless platingproduces the transparent EMI shielding material.

In general, because a catalyst for electroless plating is prepared inwater, it is not easily adhered to the base material which is smooth andhydrophobic. Thus, the base material must be pre-treated to increase itssurface roughness and hydrophilic properties by etching, etc. However,the pre-treatment cause a lack of uniformity and visibility in the basematerial surface.

Japanese Laid-Open Publication No. 2000-311527 discloses a method ofpreparing a transparent conductive film by printing a resin compositioncontaining a catalyst for electroless plating on a base material to forma pattern, and then forming a conductive metal layer on the pattern byan electroless plating method. The method is advantageous in that iteasily provides various kinds of patterned metal layers. However, anelectroless catalyst must be obtained through a complicated process, anda layer that is receptive to the resin composition must be made on thesurface of the base material before electroless plating takes place.

Japanese Laid-Open Publication No. 2001-177292 discloses a method ofpreparing the transparent conductive film by coating a hydrophobictransparent resin including a catalyst for electroless plating on thebase material, and then performing electroless plating. The transparentmetal pattern is obtained by performing electroless plating aftercoating a plating-resist compound on the resin layer, or by coating aphotoresist compound on the electroless plated surface, irradiatinglight through a photomask, and then etching. In most cases, hydrophobicresins are used to adhere to the hydrophobic base material, but themethod has a problem in that a transparent conductive film with highendurance cannot be obtained due to low adhesiveness. In addition, theprocess of shaping the metal pattern is complicated, requires expensivedevices such as a photomask, and uses a non-aqueous plating solution,thereby increasing the production costs.

Japanese Laid-Open Publication No. 2002-185184 discloses a method ofpreparing the transparent EMI shielding material by printing a resincomposition containing an electroless plating catalyst on a basematerial in a lattice pattern, and then performing electroless plating.In this case, a transparent pattern is made by a printing method,thereby requiring no expensive devices such as a photomasking machine,but a base material must be pre-treated with a receptive layer or ananchoring layer before plating in order to easily adhere the resincomposition to the base material. In particular, it takes about threedays to cure an anchoring layer coated by a two-component solution,thereby making it difficult to apply to the practical field.

SUMMARY OF THE INVENTION

A motivation of the present invention is to solve the above-describedand other problems. It is an object of the present invention to providea catalyst precursor composition for electroless plating comprising a UV(ultraviolet) curable resin with good adhesion to a base material, foreasily preparing an EMI shielding material without additionalpre-treatment of a base material.

It is another object of the present invention to provide a method ofpreparing an EMI shielding material using the catalyst precursorcomposition.

It is still another object of the present invention to provide an EMIshielding material prepared according to the method of the presentinvention.

It is still another object of the present invention to provide a PDPfilter containing the EMI shielding material.

It is another object of the present invention to provide a PDPcontaining the PDP filter.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will become more apparent by describingembodiments thereof in detail with reference to the accompanyingdrawings, in which:

FIG. 1 is a layout view of a PDP according to an embodiment of thepresent invention; and

FIG. 2 is an enlarged sectional view of a PDP filter of the PDP shown inFIG. 1.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention relates to a catalyst precursor compositioncomprising (a) a reactive oligomer; (b) a reactive monomer; (c) aphotoinitiator; (d) a catalyst precursor for electroless plating; and(e) a solvent.

The present invention relates to a method of preparing a transparent EMIshielding material by printing a catalyst precursor composition on atransparent base material in a lattice pattern, curing it with UV(ultraviolet) irradiation, and electroless plating the cured surface.

The present invention relates to a transparent EMI shielding materialprepared according to the method of the present invention.

Hereinafter, the present invention is described in more detail.

The present inventors worked to develop a catalyst precursor compositionwith high adhesiveness to a base material without the need forpre-treatment of the base material, thereby offering a simple productionmethod of EMI shielding material, and lowering the production costthereof.

In doing so, the present inventors discovered a catalyst precursorcomposition for electroless plating by dissolving an organic compound oran inorganic compound including a group VIII B or a group I B metal as acatalyst precursor in a solvent, and then printing a UV curable resinwith excellent adhesion on a base material. In addition, the presentinventors discovered that the transparent EMI shielding material isprepared by the catalyst precursor composition, because the addition ofthe UV curable resin with high adhesiveness to the base materialeliminates the need for pre-treatment of the base material.

The catalyst precursor composition for electroless plating comprises (a)a reactive oligomer; (b) a reactive monomer; (c) a photoinitiator; (d) acatalyst precursor for electroless plating; and (e) a solvent.

The transparent conductive film is prepared by printing the catalystprecursor composition on a base material in a lattice pattern, dryingit, curing it with UV irradiation, and performing electroless plating.In these processes, the catalyst precursor dissolved in the compositionis transformed into a catalyst suitable for electroless plating througha reaction initiated by UV irradiation.

The catalyst precursor exists in ion form in the composition, and isthus also referred to as “catalyst precursor ion (M^(n+)).” Examples ofthe catalyst includes Co, Rh, Ir, Ni, Pd, Pt, Cu, Ag, and Au. Thephotoinitiator is transformed to a radical by irradiating the catalystprecursor composition with UV, and then reducing the catalyst precursorion to a metal element (M⁰) which is suitable for the electrolessplating.

In addition, the present invention has an advantage in that the catalystprecursor composition contains UV curable resin with good adhesion tothe base material, thereby eliminating a need of pre-treating the basematerial with a receptive layer before electroless plating.

Hereinafter, each component of the catalyst precursor composition willbe described.

In the catalyst precursor composition of the present invention, the (a)reactive oligomer determines the basic physicochemical characteristicsof the catalyst precursor composition, such as reactivity, viscosity,surface gloss, adhesiveness, and resistance to chemicals andcontamination.

In the catalyst precursor composition of the present invention, thereactive oligomer preferably uses a material having acrylate ormethacrylate as a functional group. As examples, the reactive oligomerincludes urethane acrylate, urethane diacrylate, urethane triacrylate,urethane methacrylate, epoxy acrylate, epoxy diacrylate, polyesteracrylate, acrylic acrylate, or mixtures thereof, but is not limitedthereto.

Preferably, the reactive oligomer has a molecular weight ranging from500 to 5000. The amount of reactive oligomer can be determined dependingon the printing method. The reactive oligomer is contained at 5 to 50 wt%, preferably 20-45 wt %, with respect to total weight of the catalystprecursor composition.

The (b) reactive monomer is contained in the catalyst precursorcomposition of the present invention in order to provide easyworkability by lowering the viscosity of the reactive oligomer. Inaddition, the reactive monomer becomes a part of the cured material byparticipating in a cross-linking reaction.

The reactive monomer uses a material having acrylate or methacrylate asa functional group, for example, isobornyl acrylate, octyl acrylate,decyl acrylate, 1,6-hexanediol diacrylate, dipropylene glycoldiacrylate, tripropylene glycol diacrylate, triethylene glycoldiacrylate, tetraethylene glycol diacrylate, ethoxylated neopentylglycol diacrylate, propoxylated neopentyl glycol diacrylate,2-phenoxyethyl acrylate, propoxylated glyceryl triacrylate, ethoxylatedtrimethylolpropane triacrylate, pentaerythritol triacrylate, andmixtures thereof.

Preferably, the reactive monomer has the molecule weight ranging from100 to 600. The amount of the reactive monomer can be determineddepending on the printing method. The reactive monomer can be containedin the amount of 10 to 55 wt %, more preferably 25 to 45 wt %, withrespect to the total weight of the catalyst precursor composition.

In the present invention, the reactive oligomer and the reactive monomerhaving acrylate or methacrylate as a functional group can be used foraccelerating the reduction reaction from catalyst precursor ion (M^(n+))to catalyst precursor element (M⁰) (R. L. Jackson, J. Electrochem. Soc.1990, 137(1), 95.; Y. Nakao, J. Colloid Interface Sci. 1995, 171, 386).

In addition, the catalyst precursor composition of the present inventioncontains the (c) photoinitiator, which is dissociated to radicals by UVirradiation, and initiates the cross-linking reaction of the UV curableresin.

In addition to the basic function of the photoinitiator, thephotoinitiator in the present invention reduces the catalyst precursorion (M^(n+)) in the catalyst precursor composition to the catalystprecursor element (M⁰), which acts as a catalyst of the electrolessplating reaction.

As examples, the photoinitiator is α-hydroxyketone, phenylglyoxylate,benzildimethyl ketal, α-aminoketone, monoacylphosphine,bisacylphosphine, and mixtures thereof.

The reduction rate of the catalyst precursor ion (M^(n+)) to the element(M⁰) is dependent upon the kind of photoinitiator used. In general,α-hydroxyketone has the highest reduction rate, although the rate issomewhat different depending on the kinds of the reactive oligomer andthe reactive monomer.

The amount of the photoinitiator in the catalyst precursor compositionranges from 1.5 to 6.0 wt %, more preferably 2.5 to 4.0 wt %, withrespect to the catalyst precursor composition excluding the solvent.

In addition, the (d) catalyst precursor for electroless plating is anorganic compound or inorganic compound of a group VIII B element or agroup I B element.

In consideration of the solubility of the catalyst precursor in thesolvent, it is preferable to use an organic compound, and mostpreferably the salt of an organic compound with a carbonyl or olefingroup including Pd²⁺, such as palladium acetate, palladiumtrifluoroacetate, palladium oxalate, palladium acetylacetonate, etc.

In a certain range, the reaction rate of electroless plating isproportional to the amount of catalyst. The organic or inorganiccompound of the group VIII B metal or the group I B metal is veryexpensive, and thus it is important to optimize the amount of thecompound. In particular, although the content of the compound issomewhat different depending on the kind of electroless plating, thecatalyst precursor content is preferably 0.2 to 6.0 wt %, morepreferably 0.4 to 3.0 wt % with respect to the catalyst precursorcomposition excluding the solvent.

In addition, the (e) solvent in the catalyst precursor composition isnot particularly limited, and can be a solvent generally used in theindustrial field. Preferably, the solvent is an organic compound whichis not capable of participating in the cross-linking reaction and whichexists in a liquid phase at room temperature and 1 atmosphere. Theviscosity and surface tension of the solvent are not specificallylimited. However, the solvent needs good solubility to the catalystprecursor and photoinitiator, it should mix well with the reactiveoligomer and the reactive monomer, and have a boiling point of 60-85° C.at 1 atmosphere. A solvent with a boiling point of less than 60° C. canbe used, but it has safety problems.

Examples satisfying the solvent requirements include chloroform,acetonitrile, methylethylketone, ethylacetate, and mixtures thereof.

The amount of solvent ranges from 20 to 45 wt %, more preferably 30 to40 wt %, with respect to the total weight of the catalyst precursorcomposition.

A method of preparing an EMI shielding material with the catalystprecursor composition as described above can be summarized as the stepsof printing the catalyst precursor composition in a lattice pattern,heating it, irradiating UV thereon, and electroless plating, and isdescribed in more detail as follows.

The solution is obtained by dissolving a catalyst precursor of anorganic or inorganic compound including a group VIII B or a group I Bmetal, and a photoinitiator in solvent, and then mixing the resultantwith a reactive monomer and a reactive oligomer while stirring toprovide a catalyst precursor composition. Preferably, a vessel formixing the components of the catalyst precursor composition can be threeneck round bottom flask made of heat resistant glass, for example Pyrexglass. Because a metal stirrer can be corroded by the catalystprecursor, a Teflon (polytetrafluoroethylene) stirrer is preferable.

After preparing the catalyst precursor composition, the composition canbe printed on a base material according to the suitable method. Theprinting method is not specifically limited, but inkjet printing,gravure printing, flexo printing, and screen printing, etc. arepreferable. Based on the viscosity of the catalyst precursorcomposition, an optimal printing method can be selected. At atemperature of 25° C., a well-known printing ink has a suitableviscosity of 1 to 100 cps for inkjet printing, 30 to 300 cps for gravureprinting, 50 to 500 cps for flexo printing, and 1000 to 5000 cps forscreen printing.

The base material can be a material having sufficient transparency tovisible light, and a surface that can be easily printed with thecatalyst precursor composition, but it is not particularly limited. Theshape of the base material can be flat or it may have a curved surface.The thickness of the base material is not particularly limited. Examplesof the base material include glass, polyester, polystyrene,poly(methyl)methacrylate, polycarbonate, polypropylene, and polysulfone.Because the base material is heated and undergoes electroless platingafter printing of the catalyst precursor composition, it should have agood heat resistance and low moisture absorption. Thus, polyester ispreferable.

The solvent in the catalyst precursor composition is evaporated byheating the base material simultaneously with or shortly after printing.In the process of the evaporation, the catalyst precursor ion (M^(n+))dissolved in the solvent moves to the surface layer of the compositionin a considerable amount.

The base material is irradiated with UV when or after heating thecatalyst precursor composition. The UV irradiation causes thephotoinitiator to be dissociated to radicals which initiate across-linking reaction with the reactive monomer and the reactiveoligomer. With the cross-linking reaction, the catalyst precursor ion(M^(n+)) is reduced to catalyst metal (M⁰) which can function as acatalyst for electroless plating. Although the UV is irradiated overdifferent periods of time depending on the composition of the catalystprecursor composition, the UV is irradiated for 1 to 3 minutes. In thiscondition, energy density of the U.V ranges from 1500 to 4500 mJ/cm^(2.)

When the catalyst precursor ion (M^(n+)) is reduced to the element state(M⁰), the group VIII B or group I B metal shows its unique color on thesurface of the base material. Palladium shows silver gray.

After UV irradiation, the base material is immersed in an electrolessplating solution. The electroless plating is performed by a genericelectroless plating method, but preferables are nickel electrolessplating and copper electroless plating. In a preferred embodiment of thepresent invention, the solution for nickel electroless platingpreferably contains 16.5-18.5 g/L of NiSO₄, 29-31 g/L of NaC₆H₅O₇,8.9-9.1 g/L of NaC₂H₃O₂, 87-89 g/L of NaH₂PO₂, and 3.7-3.9 g/L of KOH.The solution for copper plating can preferably contain 4.5-5.5 g/L ofCuSO₄, 7-8 g/L of NaOH, 2-3.5 g/L of HCHO, and 30-36 g/L of EDTA.

The electroless plating reaction is usually initiated 2 to 5 minutesafter immersion, although the initiation reaction is somewhat differentdepending on the kind of plating solution. Immersion of the basematerial in the electroless plating solution for about 30 minutesproduces a plated metal layer with a thickness in the order ofmicrometers on the lattice pattern. Because the electroless platingreaction only occurs on the catalyst, the metal layer obtained byelectroless plating is only on the printed part. The metal layer is in alattice pattern, and thus has transparency and conductivity.

The EMI shielding material of the present invention has a laminatedstructure of a base material, a UV curable layer, and a plating layerfrom bottom to top. In general, the base material can preferably be atransparent material such as glass which is widely used in plasmadisplay filters.

As described in the above, the catalyst precursor composition containsthe UV curable resin with excellent adhesiveness to the base material,thereby eliminating the need for a pre-treatment step on the basematerial, to provide an easy and simple preparing method of an EMIshielding material.

In addition, the present invention provides a PDP filter comprising theEMI shield film obtained by the present invention, a near infrared rayshield film (NIR film), an anti-reflection coating film (AR film), aNeon-cut layer, a color correction layer, and a black layer.

The present invention also provides a plasma display panel containingthe plasma display filter.

FIG. 1 is a drawing of the plasma display panel according to anembodiment of the present invention. The plasma display panel of thepresent invention will now be described more fully with reference toFIG. 1. The plasma display is equipped with a case 11 for displaying apicture, an operating circuit substrate 12 equipped with electricelements for operating the panel on the back of the case 11, a panelassembly 13 showing red, green, and blue, a plasma display filter 14equipped on the front of the panel assembly 13, and a cover 15 foraccepting the plasma display panel 11, the operating circuit substrate12, the panel assembly 13, and the plasma display filter 14.

FIG. 2 is an enlarged sectional view of the plasma display filter 14shown in FIG. 1. The plasma display filter has a laminated structure ofseveral functional films on a transparent base material. With referenceto FIG. 2, the plasma display filter 14 has a laminated structure of acolor correction film 142, an EMI shield film 144, a near infrared rayshield film 146, and an anti-reflection film 148 on a transparent basematerial 140.

In the PDP filter 14, the near infrared ray shield film 146 includes anear infrared ray absorption film in which a polymer mixed with a nearinfrared ray absorption dye is coated on the transparent base material140.

The PDP of the present invention includes an EMI shield filter includingan EMI shielding material on an upper part of the panel assembly shownin FIG. 2. Accordingly, the present invention can reduce the productioncost of a PDP.

Hereinafter, the present invention is described in more detail throughexamples. However, the following examples are only for the understandingof the present invention, and the present invention is not limited bythe following examples.

EXAMPLES Example 1

A. Preparation of the Catalyst Precursor Composition

A solution was obtained by dissolving 15 g of palladium acetate and 35 gof Irgacure 184(Ciba) in 400 g of methylethylketone. While stirring thesolution, 300 g of tripropylene glycol diacrylate and 100 g ofpentaerythritol triacrylate as a reactive monomer were added. Afterhomogenizing the solution, 600 g of aliphatic urethane acrylate (Ebecryl264, SK-ucb) as a reactive oligomer was added to the mixture solution,which was then stirred to become a homogenized solution to provide acatalyst precursor composition with a viscosity of 298 cps at roomtemperature.

B. Printing of the Catalyst Precursor Composition

According to the Gravure printing method, the catalyst precursorsolution was printed on a polyester base material (SH34, SKC) in arectangular lattice pattern where the lattice had a line width of 30 μmand an interval of 300 μm. Shortly after the solvent was dried at 80°C., for 1 minute, the base material was irradiated with a UV lamp. Afterabout 2 minutes, the catalyst precursor solution was cured to a solidphase with the silver gray color of palladium.

C. Electroless Plating

The base material irradiated with UV was immersed in a Nickel platingsolution at a temperature of 50° C. After about 5 minutes, hydrogen gaswas generated on the surface of the printed pattern, which showed theinitiation of the electroless Nickel reduction reaction. After about 30minutes more, a Nickel layer of 6 μm in thickness was selectively formedto the pattern surface. As a result of a Nichiban tape test, theadhesiveness of the electroless Nickel layer to the base material wasfound to be 99/100. The manufactured transparent EMI shielding materialhad a surface resistance of 120 Ω/sq., with light transmittance of 78%.

Example 2

A. Preparation of the Catalyst Precursor Composition

A solution was obtained by dissolving 20 g of palladium acetylacetonate,30 g of Irgacure 184(Ciba), and 5 g of Irgacure TPO(Ciba) in 400 g ofchloroform. While stirring the solution, 200 g of 1,6-hexanedioldiacrylate, 250 g of dipropylene glycol diacrylate, 150 g of triethyleneglycol diacrylate, and 300 g of octyl/decyl acrylate as a reactivemonomer were added. After homogenizing the solution, 100 g of polyesteracrylate (CN2200, Sartomer) as a reactive oligomer were added to themixture solution, which was then stirred to become a homogenizedsolution to provide a catalyst precursor composition with a viscosity of4.1 cps at room temperature.

B. Print of the Catalyst Precursor Composition

The catalyst precursor solution was poured into a hollow ink cartridgefor inkjet printing, which was then installed in an inkjet printer. Theprinter and ink cartridge were a Stylus 980 printer and a T003 InkCartridge, manufactured by Epson. A computer was used to make arectangular lattice pattern with a line width of 40 μm and a lineinterval of 400 μm using the AutoCAD 2002 program of Autodesk. Thecatalyst precursor solution was printed on a polyester base material inthe lattice pattern by connecting the computer and the printer. Shortlyafter the solvent was dried at 65° C., for 1 minute, the base materialwas irradiated with a UV lamp. The UV was irradiated using opticalfiber. After about 1 minute, the catalyst precursor solution was curedto a solid phase with the silver gray color of palladium.

C. Electroless Plating

The polyester base material irradiated with UV was immersed in a Copperplating solution at a temperature of 46° C. After about 5 minutes, theplating reaction was initiated on the pattern surface. After about 30minutes more, a Copper layer of a thickness of 1.5 μm was selectivelyadhered to the pattern surface. As a result of a Nichiban tape test, theadhesiveness of the electroless Copper layer to the base material wasfound to be 99/100. The manufactured transparent EMI shielding materialhad a surface resistance of 15 Ω/sq., with light transmittance of 78%.

Measurement

The viscosity of the catalyst precursor solution was measured with aDV-II+ viscometer manufactured by Brookfield. The surface resistance andlight transmittance were measured with a Guardian232-1000 SurfaceResistivity Meter manufactured by Guardian, and a HR-100 TransmittanceReflectance Meter manufactured by Murakami Color Research Laboratory,respectively. The adhesiveness of the electroless plated metal layer tothe base material was measured by performing a Nichiban tape testaccording to JIS D0202.

Electroless Plating Solution

A Nickel electroless plating solution was prepared in the example, and aCopper electroless plating solution was purchased from Cuposit 250™(Shipley). The electroless plating solutions had the followingcompositions and conditions.

Nickel Electroless Plating Solution:

16.5-18.5 g/L of NiSO₄; 29-31 g/L of NaC₆H₅O₇; 8.9-9.1 g/L of NaC₂H₃O₂;87-89 g/L of NaH₂PO₂; 3.7-3.9 g/L of KOH. Temperature: 47-53° C.

Copper Electroless Plating Solution (Cuposit 250™)

4.5-5.5 g/L of CuSO₄; 7-8 g/L of NaOH; 2-3.5 g/L of HCHO; 30-36 g/L ofEDTA. Temperature: 43-49° C.

According to the examples in which the catalyst precursor composition ofthe present invention was printed on a base material to produce apattern, which was dried, irradiated with U.V., and then had electrolessplating performed thereto, the present invention provided a pattern ofmetals such as Nickel and Copper plated on only the pattern without anadditional pre-treatment of the base material, thereby easily preparingthe EMI shielding material. In addition, the EMI shielding material hadgood surface resistance and light transmittance.

1. A method comprising: irradiating a catalyst precursor compositionwith UV irradiation, wherein the catalyst precursor compositioncomprises: (a) a reactive oligomer which has acrylate or methacrylate asa functional group, and a molecular weight ranging from 500 to 5000; (b)a reactive monomer which has acrylate or methacrylate as a functionalgroup, and a molecular weight ranging from 100 to 600; (c)α-hydroxyketone as a photoinitiator; (d) a catalyst precursor forelectroless plating which is an organic compound or an inorganiccompound including a group VIII B metal or a group I B metal; and (e) asolvent selected from the group consisting of chloroform, acetonitrile,methylethylketone, ethylacetate, and mixtures thereof; and reducing themetal of the catalyst precursor organic compound or inorganic compoundto form a catalyst for electroless plating.
 2. The method of claim 1,wherein the (a) reactive oligomer is one selected from the groupconsisting of urethane acrylate, urethane diacrylate, urethanetriacrylate, urethane methacrylate, epoxy acrylate, epoxy diacrylate,polyester acrylate, acrylic acrylate, and mixtures thereof.
 3. Themethod of claim 1, wherein the (b) reactive monomer is one selected fromthe group consisting of isobomyl acrylate, octyl acrylate, decylacrylate, 1,6-hexanediol diacrylate, dipropylene glycol diacrylate,tripropylene glycol diacrylate, triethylene glycol diacrylate,tetraethylene glycol diacrylate, ethoxylated neopentyl glycoldiacrylate, propoxylated neopentyl glycol diacrylate, 2-phenoxyethylacrylate, propoxylated glyceryl triacrylate, ethoxylatedtrimethyloipropane triacrylate, pentaerytbritol triacrylate, andmixtures thereof.
 4. The method of claim 1, wherein the (d) catalystprecursor for electroless plating is a salt of an organic compoundincluding a carbonyl group or an olefin group, and Pd²⁺.
 5. The methodof claim 4, wherein the salt of the organic compound is one selectedfrom the group consisting of palladium acetate, palladiumtrifluoroacetate, palladium oxalate, palladium acetylacetonate, andmixtures thereof.